Rexahn Pharmaceuticals, a clinical stage biopharmaceutical company developing innovative, targeted therapeutics for the treatment of cancer, announced that updated safety and efficacy data from the ongoing phase 2a clinical trial of RX-3117 in advanced urothelial (bladder) cancer were presented at the American Society of Clinical Oncology Genitourinary Cancers (ASCO GU) 2018 Annual Meeting on February 9, 2018.

The poster presentation reported interim data on the phase 2a clinical trial of RX-3117 monotherapy for the treatment of advanced bladder cancer.  A total of 27 patients with advanced bladder cancer were enrolled into the study. Patients in the study had actively progressing bladder cancer with distant metastases to multiple sites including the liver, lung, lymph nodes and pelvis. Eighty-seven percent of the patients had received two or more prior therapies including gemcitabine (85% of patients) and immunotherapy (67% of patients).

Twenty-one patients were included in the efficacy analysis. Of these patients, 33% experienced progression free survival for two months or more and 19%, or four patients, had disease stabilization for greater than four months with one of these patients having stable disease for 301 days.  Four patients had a reduction in tumor size that was equal to or greater than 15%. RX-3117 was safe and well tolerated based on the data from the trial to date.

"The trial is still ongoing, but there is a strong efficacy signal to support further development of RX-3117 in advanced bladder cancer," said Ely Benaim, M.D., chief medical officer, Rexahn. "There is nothing approved for third line treatment of bladder cancer.  These patients are usually transferred to palliative and supportive care only, so we are very pleased with the data emerging from this study."

"Patients with advanced bladder cancer, who have already developed resistance to gemcitabine and whose cancer has progressed on immunotherapy, are very difficult to treat," said Dr. Sumanta Pal, Associate Professor at City of Hope Comprehensive Cancer Center, Duarte, California. "It was encouraging to see disease stabilization and evidence of tumor reduction in some patients. RX-3117 also appears to be safe and well-tolerated with no dose limiting side-effects."

The phase 2a clinical trial is a multicenter, open-label single-agent study of RX-3117 conducted at 5 clinical centers in the United States. Patients initially received a 700 mg daily oral dose of RX-3117, five times weekly on a three weeks on, one week off dosing schedule in a 28 day cycle for up to eight treatment cycles, or until their disease progressed. The dosing was increased to four weeks continuous treatment with no rest week for patients for whom RX-3117 was well tolerated.  The primary endpoints are an assessment of the progression free survival rate or an objective clinical response and reduction in tumor size.

The interim data from the phase 2a clinical trial of RX-3117 in advanced bladder cancer was presented on Friday February 9, 2018 in a poster presentation entitled RX-3117, an Oral Hypomethylating agent to Treat Advanced Solid Tumors: Interim Results from an ongoing phase 2a study in Advanced Urothelial Cancer (aUC).